The common starling (Sturnus vulgaris), also known as the European starling, or in the British Isles just the starling, is a medium-sized passerine bird in the starling family, Sturnidae. It is about 20 cm (8 in) long and has glossy black plumage with a metallic sheen, which is speckled with white at some times of year. The legs are pink and the bill is black in winter and yellow in summer; young birds have browner plumage than the adults. It is a noisy bird, especially in communal roosts and other gregarious situations, with an unmusical but varied song. Its gift for mimicry has been noted in literature including the Mabinogion and the works of Pliny the Elder and William Shakespeare.

The common starling has about a dozen subspecies breeding in open habitats across its native range in temperate Europe and western Asia, and it has been introduced to Australia, New Zealand, Canada, United States, Mexico, Peru, Argentina, the Falkland Islands, Brazil, Chile, Uruguay, South Africa and Fiji.[2] This bird is resident in southern and western Europe and southwestern Asia, while northeastern populations migrate south and west in winter within the breeding range and also further south to Iberia and North Africa. The common starling builds an untidy nest in a natural or artificial cavity in which four or five glossy, pale blue eggs are laid. These take two weeks to hatch and the young remain in the nest for another three weeks. There are normally one or two breeding attempts each year. This species is omnivorous, taking a wide range of invertebrates, as well as seeds and fruit. It is hunted by various mammals and birds of prey, and is host to a range of external and internal parasites.

Large flocks typical of this species can be beneficial to agriculture by controlling invertebrate pests; however, starlings can also be pests themselves when they feed on fruit and sprouting crops. Common starlings may also be a nuisance through the noise and mess caused by their large urban roosts. Introduced populations in particular have been subjected to a range of controls, including culling, but these have had limited success except in preventing the colonisation of Western Australia. The species has declined in numbers in parts of northern and western Europe since the 1980s due to fewer grassland invertebrates being available as food for growing chicks. Despite this, its huge global population is not thought to be declining significantly, so the common starling is classified as being of least concern by the International Union for Conservation of Nature.

The common starling is 19–23 cm (7.5–9.1 in) long, with a wingspan of 31–44 cm (12–17 in) and a weight of 58–101 g (2.0–3.6 oz).[15] Among standard measurements, the wing chord is 11.8 to 13.8 cm (4.6 to 5.4 in), the tail is 5.8 to 6.8 cm (2.3 to 2.7 in), the culmen is 2.5 to 3.2 cm (0.98 to 1.26 in) and the tarsus is 2.7 to 3.2 cm (1.1 to 1.3 in).[15] The plumage is iridescent black, glossed purple or green, and spangled with white, especially in winter. The underparts of adult male common starlings are less spotted than those of adult females at a given time of year. The throat feathers of males are long and loose and are used in display while those of females are smaller and more pointed. The legs are stout and pinkish- or greyish-red. The bill is narrow and conical with a sharp tip; in the winter it is brownish-black but in summer, females have lemon yellow beaks while males have yellow bills with blue-grey bases. Moulting occurs once a year- in late summer after the breeding season has finished; the fresh feathers are prominently tipped white (breast feathers) or buff (wing and back feathers), which gives the bird a speckled appearance. The reduction in the spotting in the breeding season is achieved through the white feather tips largely wearing off. Juveniles are grey-brown and by their first winter resemble adults though often retaining some brown juvenile feathering, especially on the head.[13][20] They can usually be sexed by the colour of the irises, rich brown in males, mouse-brown or grey in females. Estimating the contrast between an iris and the central always-dark pupil is 97% accurate in determining sex, rising to 98% if the length of the throat feathers is also considered.[21][22] The common starling is mid-sized by both starling standards and passerine standards. It is readily distinguished from other mid-sized passerines, such as thrushes, icterids or small corvids, by its relatively short tail, sharp, blade-like bill, round-bellied shape and strong, sizeable (and rufous-coloured) legs. In flight, its strongly pointed wings and dark colouration are distinctive, while on the ground its strange, somewhat waddling gait is also characteristic. The colouring and build usually distinguish this bird from other starlings, although the closely related spotless starling may be physically distinguished by the lack of iridescent spots in adult breeding plumage.[23]

Juvenile moulting

Like most terrestrial starlings the common starling moves by walking or running, rather than hopping. Their flight is quite strong and direct; their triangular-shaped wings beat very rapidly, and periodically the birds glide for a short way without losing much height before resuming powered flight. When in a flock, the birds take off almost simultaneously, wheel and turn in unison, form a compact mass or trail off into a wispy stream, bunch up again and land in a coordinated fashion.[20]Common starling on migration can fly at 60–80 km/h (37–50 mph) and cover up to 1,000–1,500 km (620–930 mi).[24]

Several terrestrial starlings, including those in the genus Sturnus, have adaptations of the skull and muscles that help with feeding by probing.[25] This adaptation is most strongly developed in the common starling (along with the spotless and white-cheeked starlings), where the protractor muscles responsible for opening the jaw are enlarged and the skull is narrow, allowing t